‘I love it when you see a sign that says “Dangerous Building – Do Not Enter”,’ says Veranique Dron as we walk back down from the hill overlooking Edinburgh’s Barnton Quarry. ‘“Building at risk” – it’s only an invitation.’ From the crest of that hill Dron has just shown me the drab single-storey exterior of the former ROTOR station buried deep within the quarry, a Cold War-era radar defence station built in the 1950s but more famous locally for its latter use as a nuclear bunker.

Yet it’s been many decades since Khrushchev had his finger on the button and Barnton Quarry has long been closed and abandoned. Now its crumbling, flat-roofed upper level appears mouldy with undergrowth from this distance, and every exterior wall is daubed with graffiti, much of it the recognisable work of the city’s more skilful street artists. Dron says she’s been in there before, exploring all three subterranean floors of the base, but doing anything more than looking at it from here will be a step too far for my first ‘urban explore’. This building has already broken Dron’s coccyx on an earlier visit, and she says she wouldn’t go in without some form of respiratory protection: asbestosis is one of the Urban Explorer’s most significant enemies.

Urban exploration is by no means a new art form, but the internet has lent the practice of entering and exploring abandoned buildings new life. Many of those who engage in it have some level of photographic experience (including Dron, who spent a year photographing wildlife in Kenya professionally), and there are more and more Flickr feeds and Facebook pages devoted to cataloguing spaces which are no longer in use, a ghostly alternative tourist trail dedicated to grimly beautiful stately homes, train stations, amusement parks and underground tunnels which have, in many cases, been boarded up and left to rot.

Our next stop on a Sunday afternoon trail which takes us along the path of the A9 and the Forth Valley is the former Manuel brickworks near the village of Whitecross, now just a series of grey concrete footprints in the ground. The brickworks’ red Victorian warehouses were of little interest to Dron before they were demolished – the grey granite pillar of Haining Castle’s remains at the corner of the site is what we’ve come to see, a construction Dron says should be incorporated into the developer’s plans for the site now she’s brought its historical value to their attention. ‘They used to make buildings with walls ten feet thick,’ she says. ‘This is what we should be preserving, not flimsy single-skin buildings from the last century.’

Lately sites such as Dron’s and a recently established Facebook group run by a collective known only as Abandoned Scotland have begun to shed light upon the derelict urban and rural spaces of Scotland, of which there are surprisingly many. Dron has been doing this for around six years, after an inquisitive visit to her local Bangour Village Hospital – or ‘Bangour Asylum’ – in West Lothian fired her passion, and she says she’s seen around a thousand such spaces since.

Next on the list is a stately home near Polmont with metal-shuttered windows and a subsidence problem from the landfill next door, its arched gatehouse almost as grand as the house itself. Before we enter the overgrown driveway Dron stops at the neat new-build bungalow on the main road and asks permission from the former occupants to go in. While by its very nature Urban Exploration involves entering places where you aren’t necessarily wanted, Dron’s job as an immigration officer with the UK Border Agency (which she’s since left: ‘it was crucifying’) means she always stays on the right side of the law.

‘I love it when people come up to you and say “this is private property”,’ she says, rolling her eyes. ‘I think you’ll find it’s not.’ She uses Scotland’s Freedom to Roam law to her advantage, but more importantly never damages a site, enters by force or removes anything from it. If she can request the owner’s permission or convince a friendly security guard she really does just want to look around, so much the better.

Why does she do it? ‘To document these places before they’re gone,’ she says simply. Although she seems like the adventurous sort, at one point comparing her hobby to going off into the woods to explore as a child, Dron almost seems to look on it as if it were a public service. In many ways it is: while plenty of the empty spaces she revisits regularly may have some level of listing from Historic Scotland (Dron refers to them as ‘Hysterical Scotland’, indicating a relationship which isn’t always entirely cordial), current financial necessities must make it hard for the Governmental body to observe and maintain every single property in their portfolio.

So Dron and other like-minded Urban Explorers seem to treat what they do almost as if it were an unofficial inspection job, informing Historic Scotland if any sites undergo a marked deterioration, campaigning with owners and developers to save certain buildings and regularly updating the online Buildings at Risk Register for Scotland, a bible (though not a comprehensive one) for Urban Explorers in Scotland. The fact is, though, not everywhere can be listed or saved, and Dron compares the experience of returning to buildings to watch them crumble to that of watching an old friend die slowly.

‘Many of these buildings are unique,’ says an anonymous respondent to the Abandoned Scotland email address on behalf of the group, ‘such as the twin towers of [Lanarkshire former asylum] Hartwood Hospital. In modern days you would rarely see such a building being erected and so many of them could be renovated and put to use for modern purposes. However, it all comes down to cost. It makes you wonder, if a little more effort was made to maintain them in the first place then what could the possibilities be for their future?’

‘It’s to do with economics, of course,’ says David Johnston, highly regarded in the interlinked worlds of exploration and restoration following his decision to buy Angus’ stunning Balintore Castle following a compulsory purchase from its absentee landlords by the local authorities. ‘But Councils could help by bringing in compulsory purchases to allow individuals with good will to rescue these buildings.’

If Dron has a pet building of her own it seems to be the 16th century New Slains Castle in Aberdeenshire, the clifftop-clinging remains of which apparently inspired Bram Stoker to write Dracula as much as Romania’s Bran Castle. It’s this kind of tourist-friendly heritage which she says can be exploited in order to save and regenerate these buildings, the oldest of which she loves as much as she hates modern architecture.

Our final stop is Dunmore Park House near Airth, a well-preserved shell of a building which has been partially demolished for redevelopment. Dron shows me the underground warren of tunnels used for housing slaves and the telltale signs of a ‘soft floor’ in the nearby stable blocks (check the lower floor ceiling for signs of damp first), and explains how she wants to raise awareness of urban exploration as a means of maintaining contact with our heritage.

She tells me she much prefers older buildings in the country away from the bustle of the city. ‘Although there is an underground railway station in Edinburgh,’ she begins. Oh yeah? Where is it? She laughs. ‘Now that one really is a secret!’

Veranique Dron’s Flickr feed is at flickr.com/people/kylie6470clanurbex

Find more information at facebook.com/AbandonedScotland

Dunmore Park House

New Slains Castle

Bangour Asylum villas

Avondale House